/*
 * Copyright 2006 Mark Bakker <bakker.mark AT gmail.com>
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */
package com.google.gwt.vector.client.ui;

import com.google.gwt.user.client.Element;
import com.google.gwt.user.client.ui.ComplexPanel;
import com.google.gwt.user.client.ui.Widget;

/**
 *
 */
public abstract class VectorWidget extends ComplexPanel {

  private VectorWidget parent = null;

  private VectorWidget() {
    super();
  }

  protected VectorWidget(Element elem) {
    this();
    setElement(elem);
  }

  public void add(Widget w) {
    if (w instanceof VectorWidget) {
      super.add(w, this.getElement());
    } else {
      throw new UnsupportedOperationException("This panel only supports widgets of the type 'VectorWidget'");
    }
  }

  public VectorWidget getParentPanel() {
    return parent;
  }

  protected void setParentPanel(VectorWidget parent) {
    this.parent = parent;
    if (parent == null) {
      onDetach();
    } else if (parent.isAttached()) {
      onAttach();
    }
  }

}
